I've decided not to pursue trying to get those missing photos back. I have done what you suggested above and what someone else suggested but I'm guessing the problem is to do with the database after the switch to phpbb3. Not to worry, members just need to upload their photos again.
While I'm here I edited the contrast template css to blend the gallery into my forum a bit more. I have everything the way I like it except that the text for the comments left are white. I can change this colour by editing one of the small, medium or large text attributes in the css. can't remember which one. But when I change the colour to something other than white it also changes the text somewhere else.
Is there a way just to change the colour of the text for the comments without affecting anywhere else?